I don't think most people can actually do that. In theory people can do all kinds of things, but each person in this universe is constrained by all kinds of things like instinct, resources, and what they actually experience etc.

So, among the things 75% of the people alive today might actually do, browsing Facebook might actually be the worst. Depending on your value system.

Well under 1/2 the worlds population cheats at any point in their lives, that number is not going to change any time soon.

The number of possible Alcoholics don't add up to 75% of the global population. Sexual harassment while bad is not really a temptation for most people. Stealing, is again not things most people even consider.

EX: I may not be average, but I am not in a relationship so I can't exactly cheat. I don't like Alcohol so I am not going to become an Alcoholic. I could go on, but things are really not in my realm of possibility right now.